import java.util.Arrays;

public class O61 {
    public static void main(String[] args) {
        O61 o = new O61();
        System.out.println(o.isStraight(new int[]{1,2,3,4,5}));
    }
    public boolean isStraight(int[] nums) {
        Arrays.sort(nums);
        int w = 0,c = 0;
        if (nums[3]==0)
            return true;
        for (int i = 0; i < nums.length-1; i++) {
            if (nums[i]==0)
                w++;
            else if (nums[i+1]==nums[i]){
                return false;
            }else {
                c+=nums[i+1]-nums[i]-1;
            }
        }
        return w>=c;
    }
}
